10-38 Testing and Troubleshooting Date Code 20080110
SEL-387E Instruction Manual
Step 5.
Purpose: Verify the Level 1 volts/hertz delay setting.
Method: Execute the
SHOWSET
command via the relay front panel or serial port
and verify the setting (i.e.,
SHO 24D1D <Enter>
).
Step 6.
Purpose: Display the appropriate Relay Word bit on the front-panel LEDs.
Method: Execute the
TARGET
command (i.e.,
TAR F 24D1T <Enter>
). The
SEL-387E Relay now displays the state of the volts/hertz elements on the
bottom row of front-panel LEDs.
Step 7.
Purpose: Apply balanced three-phase voltage and change the voltage until the
appropriate LED illuminates.
Method: Apply balanced three-phase voltages as shown in
Figure 10.5. Change the
voltage to a value above the
24D1P
setting. The
24D1T
LED should
illuminate
24D1D
seconds later, ±0.1% of setting ±4.2 ms (at 60 Hz).
Step 8.
Purpose: Verify the Level 2 volts/hertz pickup setting,
24D2P1
.
Method: Execute the
SHOWSET
command via the relay front panel or serial port
and verify the setting (i.e.,
SHO 24D2P1 <Enter>
).
Step 9.
Purpose: Display the appropriate Relay Word bit on the front-panel LEDs.
Method: Execute the
TARGET
command (i.e.,
TAR F 24C2 <Enter>
). The
SEL-387E Relay now displays the state of the volts/hertz elements on the
bottom row of front-panel LEDs.
Step 10.
Purpose: Apply balanced three-phase voltage and change the voltage until the
appropriate LED illuminates.
Method: Apply balanced three-phase voltages as shown in
Figure 10.5. Change the
voltage to a value above the
24D2P1
setting until the
24C2
LED
illuminates. The
24C2
pickup should be ±1% of setting.
Calculate
pickup voltage as:
NFREQ•PTR•3
V•freq•1P2D24•10
V
nom
sec
=
V
sec
= Secondary Voltage (applied)
PTR = Potential transformer ratio (Setting)
freq = Frequency (applied)
NFREQ= Nominal Frequency (Setting)
V
nom
= Nominal Voltage in kV (Setting)
To Next Page
Loading...
